When adhering a collecting device to human skin the major situations that need to be considered are the following:
1) Wearing the adhesive; the adhesive should stay in place and not detach or fall off because of skin or body movements.
2) Removing the adhesive; the adhesive should be easy to remove without excessive pain or skin damage as a result.
This is a paradox—the adhesive should stay in place nicely, but should also be easy to remove. The solution today is a compromise in adhesive characteristics that accommodate both situations.
The soft adhesive systems have shown to be advantageous in the use as a skin friendly adhesive wafer.
New opportunities are obtained using a permeable adhesive material to design a skin friendly adhesive wafer. The load of filler in order to handle moisture from the skin is lower thereby increasing the softness of the adhesive. Moisture permeable materials can be formulated to be very soft as a material property. This is the main factor in order to design a soft adhesive system. Furthermore, permeable films can also be formulated with very soft properties and thus the adhesive wafer construction can be designed with a certain softness. As for wearing a soft adhesive wafer on the skin (in contrast to a standard hydrocolloid wafer) a high degree of comfort and security is obtained, as the soft adhesive wafer will be able to follow the body movements without having the feeling that the adhesive will peel off.
The construction described in International Patent Application No. PCT/DK2008/050148 is a two layer adhesive construction of a soft water impermeable, moisture permeable skin facing adhesive that allows the moisture from the skin to diffuse through the adhesive material. The construction further comprises a non skin facing layer that is water impermeable, moisture permeable containing absorbing particles allowing the moisture to be absorbed in the particles.
There has now surprisingly been found a way to isolate the two situations mentioned above, such that the ability of the soft adhesive to be easily removed can be controlled independently of the ability of the soft adhesive to stay in place.